Use of "localtime" without parentheses is ambiguous

2.011 introduced a regression with commit 58d789e3015978ac746adc6525422e3702c6d77b.  The use of `localtime` without parentheses triggers a warning in older versions of Perl (e.g. [this CPAN Testers report](http://www.cpantesters.org/cpan/report/5ae4e6b8-780e-11e4-b483-cd3ee0bfc7aa)).